Project Summary/Abstract The etiology and natural history of urologic chronic pelvic pain syndromes (UCPPS) are not well understood. Along with other MAPP Research Network sites, the University of Iowa will perform a longitudinal, phenotyping study of UCPPS symptom patterns. Within this Trans-MAPP study, we will characterize the role of neuroinflammation and hypothalamic pituitary axis (HPA) dysregulation in UCPPS symptoms and symptom change. The central hypothesis of this work is that toll-like receptor (TLR)-4 activation and (HPA) dysregulation are key underlying features of UCPPS and will be associated with UCPPS symptom changes, flares and disease progression. To test this hypothesis, men and women with UCPPS will be enrolled into the 36-month Symptom Patterns Study, in which symptoms, symptom change and flare frequency and severity will be characterized (Aim 1). In-person and internet-based questionnaires will be collected every 3 months. Complementary Trans-MAPP research will determine the role of inflammatory biomarkers, and stress pathways with respect to urological and non-urological longitudinal symptom patterns and flares (Aim 2); develop, test and use a mobile application to provide real-time, ecological momentary assessments of pain and associated symptoms (Aim 3); perform brain magnetic resonance imaging to determine whether acute stress- evoked pain modulates brain networks and if changes in functional connectivity are predictive of long-term pain symptom change (Aim 4); and use preclinical UCPPS mouse models to determine whether TLR-2/TLR-4 sensitization is mechanistically linked to pain and voiding dysfunction (Aim 5). The work proposed will provide an integrated assessment of disease biomarkers, genetic predictors, real-time symptom measurement and brain structure/function in men and women with UCPPS and their associations with UCPPS symptom changes over time. In the animal model we will explore potential translational therapeutic approaches based on TLR-4 modulation. These Trans-MAPP study results will not only identify neuroinflammatory phenotypes related to symptom improvement, worsening, and flares but will also reveal mechanisms by which targeted UCPPS therapy may eventually be implemented.